-LRB- CNN -RRB- -- Swimmer Michael Phelps , the most-decorated Olympian of all time , tweeted Sunday that he is taking a break from the sport `` to attend a program that will provide the help I need to better understand myself . ''

According to his official Twitter account , `` Swimming is a major part of my life , but right now I need to focus my attention on me as an individual . ''

The decision comes after he was charged last week with driving under the influence of alcohol , excessive speed and crossing double lines on Interstate 95 in Baltimore .

The 22-time Olympic medalist , 29 , was arrested Tuesday about 1:40 a.m. and later released , police said . According to media reports , police said his blood-alcohol content was .14 .

Last week 's arrest is not Phelps ' first run-in with the law

In 2004 , he was arrested on charges of driving under the influence in Salisbury , Maryland . He pleaded guilty and was sentenced to 18 months probation . He also issued an apology after that incident .

Five years later , a photograph of him smoking marijuana at a party surfaced .

`` I 'll make a million mistakes in my life , but as long as I never make the same mistake again , then I 've been able to learn and grow , '' Phelps said in 2012 . He also said that the incident made him realize who his real friends were .

Of Phelps ' record-smashing 22 Olympic medals , 18 are gold , including the eight he won in 2008 at the Beijing Olympics .

Phelps returned to competitive swimming in April and raced for the United States in August at the Pan Pacific Swimming Championships , his first international meet since the Olympics -LRB- and two years before the next Games in Brazil -RRB- .

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Phelps tweets that he will get `` the help I need to better understand myself ''

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He was arrested early Tuesday , accused of driving with a blood-alcohol level of .14

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Olympic medalist returned to competitive swimming in April